<!doctype html>
<html lang="en">
	<head>
		<meta charset="UTF-8">
		<title>Document</title>
		<style>
			div {
				width: 100px;
				height: 50px;
				background: yellow;
				border: 1px solid black;
				color: black;
				float: left;
				margin: 10px;
				line-height: 50px;
				text-align: center;
			}
		</style>
		<script src="js/jquery-1.12.1.js"></script>
		<script>
			$(function() {
				$(".menu:first").css({
					"color": "red"
				});
			})
		</script>
	</head>
	<body>
		<div class="menu">菜单1</div>
		<div class="menu">菜单2</div>
		<div class="menu">菜单3</div>
		<div class="menu">菜单4</div>
		<div class="menu">菜单5</div>
		<div class="menu">菜单6</div>
	</body>
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